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Using the full-potential linearized augmented plane-wave method of first-principles calculations of density functional theory, we have performed a systematic investigations on the structural, electronic, and magnetic properties related to the spintronic applications for gallium phosphide GaP doped with 3 d transition metal (TM) atoms such as vanadium (V), chromium (Cr), and manganese (Mn) as ternary GaGa TMP diluted magnetic semiconductors (DMSs) in zinc-blende phase at concentrations x = 0.0625, 0.125, and 0.25. The analysis of electronic and magnetic properties with various concentrations ( x) of TM revealed that GaGa VP at ( x = 0.0625, 0.125, and 0.25) and Ga TMP (TM = Cr and Mn) at ( x = 0.0625 and 0.125) are half-metallic ferromagnets (HMF) with spin polarization of 100 %. The HMF character destroyed for GaGaCrP and GaGaMnP at higher concentration x = 0.25 of Cr and Mn. The half-metallic gap increases with decreasing in concentration of impurity, and therefore, the GaGa TMP, GaGaCrP, and GaGaMnP DMSs at low concentrations appear to be better candidates for spintronic applications. [ABSTRACT FROM AUTHOR]

The structural, electronic, and half-metallic ferromagnetic properties of ordered zinc blende Al Mn P diluted magnetic semiconductors with concentrations ( x = 0.0625, 0.125, and 0.25) are studied using first-principle calculations of density functional theory in order to seek out the possibility to use these materials for the spin injection in the field of spintronic applications. The electronic structures of Al Mn P at all concentrations exhibit a half-metallic ferromagnetic behavior with 100 % magnetic spin polarization and half-metallic gap. While, the analysis of partial densities of states reveals that strong hybridization between 3 p (P) and 3 d (Mn) partially filled states dominates the gap, which stabilizes the ferromagnetic state configuration associated with double-exchange mechanism. Also, the magnetic proprieties prove an integer total magnetization of 4 u that confirms the half-metallic ferromagnetic feature of Al Mn P compounds. [ABSTRACT FROM AUTHOR]

First-principle calculations within the framework of density functional theory are employed to study the structural, electronic, and half-metallic ferromagnetic properties of In (TM)P (TM = Cr, Mn) at concentrations (x = 0.0625, 0.125, 0.25)of transition metal in zinc blende phase. The investigations of electronic and magnetic properties indicate that InTMP (TM = Cr, Mn) at x = 0.0625, 0.125, and 0.25 are half-metallic ferromagnets with 100 % magnetic spin polarization. On the one hand, the total magnetization is an integer Bohr magneton of 3 μ and 4 μ for InCrP and InMnP, respectively, which confirms the half-metallic feature of InTMP compounds. On the other hand, the densities of states of majority-spin states show that the large hybridization between 3p (P) and 3d (TM) partially filled states dominates the gap, which stabilizes the ferromagnetic state configuration associated with double-exchange mechanism. The band structures depict that half-metallic gap at x = 0.0625 is 0.404 eV for InCrP which is higher than 0.125 eV for InMnP. Therefore, the largest half-metallic gap in InCrP at low concentration x = 0.0625 reveals that Cr-doped InP seem to be a more potential candidate than that Mn-doped InP for spin injection applications in the field of spintronic devices. [ABSTRACT FROM AUTHOR]

Background: Mental disorders in the workplace are a major public health problem. Knowledge of the impact of the psychosocial work environment on mental and behavioral disorders can assist occupational physicians in the identification and description of occupational risk situations, and help to define priority actions. However, no classification for occupational exposure factors is currently available. We aimed to build a thesaurus of "Organizational, Relational, Ethical and other Contributing Factors" (FOREC) linked with the onset of mental and behavioral disorders., Methods: The French Agency for Food, Environmental and Occupational Health and Safety (ANSES) initiated and supervised a multidisciplinary working group consisting of the representatives of the main French occupational and public health actors. All decisions were accepted on a consensus basis. This collaborative work led to the classification of occupational exposure factors for mental and behavioral disorders in the workplace. To test this thesaurus in clinical practice, a French multicenter study was implemented. Patients were workers referred to the Occupational Disease Centers for mental health issues at work. Factors contributing to mental and behavioral disorders among workers were identified and coded retrospectively from the worker's point of view using the FOREC thesaurus., Results: We recruited 323 workers, aged 44.9±9.2 years, of which 31.3% were men. The most commonly encountered disorders were generalized anxiety disorders (106 workers, 32.8%) and moderate depressive episodes (86 workers, 26.7%). We identified 1357 factors, i.e. an average of 4.2 factors per worker. Among them, 575 (42.4%) were relational and 515 (37.9%) were organizational. All factors identified during consultations were described in the thesaurus., Conclusions: We built the first thesaurus of "Organizational, Relational, Ethical and other Contributing Factors" (FOREC) that may help to generate profiles of mental and behavioral disorders at work. Encoding and describing these exposure factors, as well as using a worldwide standardized and shared terminology, will help to identify specific workplace prevention programs., Competing Interests: The authors have declared that no competing interests exist.

Newly identified spore-forming pigmented marine bacteria, Bacillus indicus HU36 and Bacillus firmus GB1, are sources of carotenoids (mainly 15 yellow and orange pigments and 13 pink pigments, respectively) with original structures. These bacterial carotenoids were evaluated for their ability to inhibit the iron-induced peroxidation of linoleic acid micelles, or sunflower oil-in-water emulsions, in comparison with β-carotene, lycopene and astaxanthin. Lipid peroxidation was carried out in acidic conditions and initiated by dietary heme or non-heme iron (metmyoglobin or Fe(II), respectively) so as to simply simulate the postprandial gastric medium, a possible site for dietary oxidative stress. Lipid hydroperoxide formation and carotenoid consumption were followed by UV-vis spectroscopy and appropriate indicators of the antioxidant activity were estimated in each model. The bacterial carotenoids were found to be better inhibitors of heme-induced lipid peroxidation than the reference carotenoids as a likely consequence of their location closer to the interface in micelles and lipid droplets. However, this trend was not confirmed in lipid peroxidation induced by non-heme iron, possibly because of the redox recycling of Fe(II) by carotenoids. The quantitative kinetic analysis of the peroxidation curves suggests that the carotenoids mainly inhibit the propagation phase of lipid peroxidation by direct scavenging of the lipid peroxyl radicals, in agreement with independent experiments showing that carotenoids are unable to reduce the one-electron oxidized form of metmyoglobin (ferrylmyoglobin), a model of initiating species in heme-induced lipid peroxidation. Overall, carotenoids from Bacillus indicus HU36 and Bacillus firmus GB1 were found to be interesting antioxidants to fight postprandial oxidative stress in the stomach.